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排序方式: 共有177条查询结果,搜索用时 15 毫秒
151.
Luisa Airoldi Cinzia Magagnotti Angela Rita Iannuzzi Cristina Marelli Renzo Bagnati Roberta Pastorelli Alessandro Colombi Stefano Santaguida Chiara Chiabrando Silvia Schiarea Roberto Fanelli 《Biochemical and biophysical research communications》2009,381(3):397-1159
In this pilot study we used a proteomic approach to compare the urinary protein patterns of healthy smokers and non-smokers. Proteins were resolved by two-dimensional gel electrophoresis and identified by mass spectrometry. The relative abundance of three inflammatory proteins (S100A8, inter-alpha-trypsin inhibitor heavy chain 4, CD59) and that of two isoforms of pancreatic alpha amylase was significantly higher in smokers. Zinc-alpha-2-glycoprotein was the only protein down-regulated in smokers. Its abundance was significantly correlated with urinary glucocorticoids. Most of the proteins identified may be non-specific biomarkers of tobacco effects, since they are involved in inflammatory responses associated with several diseases. Of greater interest are the changes in abundance of pancreatic alpha amylase and zinc-alpha-2-glycoprotein, which after proper validation, might be candidate biomarkers of diseases resulting from exposure to tobacco smoke. The data also show for the first time that smoking can affect the expression profile of urinary proteins. 相似文献
152.
153.
Expression of N-linked sialyl Le(x) determinants and O-glycans in the carbohydrate moiety of human amniotic fluid transferrin during pregnancy 总被引:3,自引:0,他引:3
Transferrin, a glycoprotein involved in iron transport in body fluids, was
isolated from amniotic fluid of a hydramniospatient by sequential
anion-exchange chromatography and gel filtration. The N-glycans of human
amniotic fluid transferrin (hAFT) were enzymatically liberated by PNGase-F
digestion, isolated by gel filtration and fractionated by (high-pH)
anion-exchange chromatography. After alkaline borohydride treatment of
native hAFT, the released O-glycans were isolated by gel filtration and
fractionated by anion-exchange chroma-tography. Structure elucidation of 14
N- and 2 O-glycans was performed by 500 or 600 MHz1H-NMR spectroscopy.
Besides conventional N-glycans established earlier for human serum
transferrin (hST), new (alpha1-3)-fucosylated N- glycans were found,
representing sialyl Le(x) elements. Furthermore, as compared to hST, a
higher degree of (alpha1-6)-fucosylation and an increase in branching from
di- to triantennary compounds has been detected. The presence of O-glycans
is demonstrated for the first time in transferrin.
相似文献
154.
155.
Evolutionary transfer of ORF-containing group I introns between different subcellular compartments (chloroplast and mitochondrion) 总被引:10,自引:2,他引:8
Turmel M; Cote V; Otis C; Mercier JP; Gray MW; Lonergan KM; Lemieux C 《Molecular biology and evolution》1995,12(4):533-545
We describe here a case of homologous introns containing homologous open
reading frames (ORFs) that are inserted at the same site in the large
subunit (LSU) rRNA gene of different organelles in distantly related
organisms. We show that the chloroplast LSU rRNA gene of the green alga
Chlamydomonas pallidostigmatica contains a group I intron (CpLSU.2)
encoding a site-specific endonuclease (I-CpaI). This intron is inserted at
the identical site (corresponding to position 1931-1932 of the Escherichia
coli 23S rRNA sequence) as a group I intron (AcLSU.m1) in the mitochondrial
LSU rRNA gene of the amoeboid protozoon Acanthamoeba castellanii. The
CpLSU.2 intron displays a remarkable degree of nucleotide similarity in
both primary sequence and secondary structure to the AcLSU.m1 intron;
moreover, the Acanthamoeba intron contains an ORF in the same location
within its secondary structure as the CpLSU.2 ORF and shares with it a
strikingly high level of amino acid similarity (65%; 42% identity). A
comprehensive survey of intron distribution at site 1931 of the chloroplast
LSU rRNA gene reveals a rather restricted occurrence within the
polyphyletic genus Chlamydomonas, with no evidence of this intron among a
number of non- Chlamydomonad green algae surveyed, nor in land plants. A
parallel survey of homologues of a previously described and similar
intron/ORF pair (C. reinhardtii chloroplast CrLSU/A. castellanii
mitochondrial AcLSU.m3) also shows a restricted occurrence of this intron
(site 2593) among chloroplasts, although the intron distribution is
somewhat broader than that observed at site 1931, with site-2593 introns
appearing in several green algal branches outside of the Chlamydomonas
lineage. The available data, while not definitive, are most consistent with
a relatively recent horizontal transfer of both site-1931 and site- 2593
introns (and their contained ORFs) between the chloroplast of a
Chlamydomonas-type organism and the mitochondrion of an Acanthamoeba- like
organism, probably in the direction chloroplast to mitochondrion. The data
also suggest that both introns could have been acquired in a single event.
相似文献
156.
The robustness of two phylogenetic methods: four-taxon simulations reveal a slight superiority of maximum likelihood over neighbor joining 总被引:6,自引:3,他引:3
The robustness (sensitivity to violation of assumptions) of the maximum-
likelihood and neighbor-joining methods was examined using simulation.
Maximum likelihood and neighbor joining were implemented with Jukes-
Cantor, Kimura, and gamma models of DNA substitution. Simulations were
performed in which the assumptions of the methods were violated to varying
degrees on three model four-taxon trees. The performance of the methods was
evaluated with respect to ability to correctly estimate the unrooted
four-taxon tree. Maximum likelihood outperformed neighbor joining in 29 of
the 36 cases in which the assumptions of both methods were satisfied. In
133 of 180 of the simulations in which the assumptions of the
maximum-likelihood and neighbor-joining methods were violated, maximum
likelihood outperformed neighbor joining. These results are consistent with
a general superiority of maximum likelihood over neighbor joining under
comparable conditions. They extend and clarify an earlier study that found
an advantage for neighbor joining over maximum likelihood for
gamma-distributed mutation rates.
相似文献
157.
C Tardif H Maamar M Balfin JP Belaich 《Journal of industrial microbiology & biotechnology》2001,27(5):271-274
Electropermeabilization of Clostridium cellulolyticum was optimized using ATP leakage assays. Electrotransformation was then performed under optimized conditions (6 to 7.5 kV
cm−1 field strength applied during 5 ms to a mixture containing methylated plasmids and late exponential phase cell suspensions
(10 molecules:1 cell) in a sucrose-containing buffer). Transformants were only obtained when 7 or 7.5 kV cm−1 pulses were applied. Transformation efficiencies evaluated from the growth curves of transformed cells were between 105 and 107 transformants per microgram of plasmid DNA for five different replicon-based plasmids. Restriction nuclease digestion patterns
of pJIR418 purified from transformed Clostridia and Escherichia coli were indistinguishable, indicating that heterologous DNA was structurally stable in the Clostridium strain. Copy numbers of 130, 70 and 10 were estimated from purification yield for pCTC1, pKNT19 and pJIR418, respectively.
Journal of Industrial Microbiology & Biotechnology (2001) 27, 271–274.
Received 12 September 2000/ Accepted in revised form 25 November 2000 相似文献
158.
Varalli M Marelli G Maran A Bistoni S Luzzana M Cremonesi P Caramenti G Valgimigli F Poscia A 《Biosensors & bioelectronics》2003,18(7):899-905
The aim of this study was to evaluate the reproducibility, the accuracy and the reliability of a continuous subcutaneous glucose measuring system. The GlucoDay system (A. Menarini I.F.R. S.r.l.-Florence, Italy) is a portable instrument provided with a micro-pump and a biosensor, coupled to a microdialysis system (see part 1). This instrument has demonstrated high reliability coupled with a low degree of invasivity. The profiles of glucose monitoring allow to achieve an excellent knowledge of the real variation of glucose in diabetic patients. The reproducibility study showed a bias lower than 10% between instruments. The accuracy study showed a difference from the reference method lower than 15%. 相似文献
159.
Publication of the complete diploid genome sequence of the yeast Candida albicans will accelerate research into the pathogenesis of Candida infections. Comparative genomic analysis highlights genes that may contribute to C. albicans survival and its fitness as a human commensal and pathogen. 相似文献
160.
Belkis E. Marelli Cristian J.M. Leiva Rocío B. Flores Brun Cintia S. Ramírez Juan I. Failla Valentina Matiller Ayelén N. Amweg Florencia Rey Hugo H. Ortega 《Reproductive biology》2018,18(4):432-439
In ovarian granulosa cells, follicle-stimulating hormone (FSH) regulates the proliferation and differentiation events required for follicular growth and oocyte maturation. FSH actions are mediated exclusively through the FSH receptor (FSHR). In cattle, the FSHR gene expression pattern during folliculogenesis and the implications of this receptor in reproductive disorders have been extensively studied. However, the limited availability of specific antibodies against bovine FSHR has restricted FSHR protein analysis. In the present study, we developed an anti-FSHR polyclonal serum by using a 14-kDa peptide conjugated to maltose binding protein. The antiserum obtained was characterized by western blot of protein extracts from bovine follicles, BGC-1 cells and primary cultures of granulosa cells stimulated with testosterone. Also, the blocking effect of serum on estradiol secretion and cell viability after gonadotropin stimulus was characterized in a functional in vitro assay. A 76-kDa protein, consistent with the predicted molecular size of full-length FSHR, was detected in ovarian tissue. Besides, two immunoreactive bands of 60-kDa and 30-kDa (only in cultured cells) were detected. These bands would be related to some of the isoforms of the receptor. Therefore, immunohistochemical assays allowed detecting FSHR in the cytoplasm of granulosa cells and an increase in its expression as follicles progressed from primordial to large preantral follicles. These results suggest that the anti-FSHR serum here developed has good reactivity and specificity against the native FSHR. Therefore, this antiserum may serve as a valuable tool for future studies of the biological function of FSHR in physiological conditions as well as of the molecular mechanism and functional involvement of FSHR in reproductive disorders. 相似文献